Several empirical studies have suggested that self-monitoring is an effective strategy to increase appropriate behavior in children and adults with developmental disabilities. Results of a comprehensive review of self-monitoring research with people who have developmental disabilities revealed that 71% of the participants were trained by researchers. However, researchers are not typical intervention agents. To ensure that people who are typically in the participant’s environment (e.g., teachers, parents, caregivers) can effectively teach people with developmental disabilities to self-monitor and that this in turn will change the participant’s behavior, it is important that research examine the effectiveness of self-monitoring when the training is provided by typical intervention agents. Thus, the purpose of this dissertation study was to investigate the effects of a self-monitoring intervention package on both teacher and student behavior in the classroom. The self-monitoring intervention package consisted of training teachers to use self-monitoring, providing feedback on the self-monitoring intervention developed by the teacher, providing feedback to teachers while training the student to self-monitor, and providing feedback to teachers while they implemented the self-monitoring intervention in the classroom. During intervention, the researchers provided feedback to teachers to ensure that teachers were correctly instructing the students to self-monitor. Teachers then implemented the self-monitoring intervention without researcher feedback (maintenance). Teachers required very little to no feedback after the self-monitoring training, feedback on the self-monitoring intervention they developed, and student self-monitoring training. The researcher provided immediate feedback during the first session when the self-monitoring intervention was implemented in the classroom to ensure the teachers implemented the self-monitoring intervention with fidelity. Rate of inappropriate sitting decreased for all students after the self-monitoring intervention was introduced, and the percentage of non-overlapping data metric values indicated that the self-monitoring interventions were highly effective for three participants and effective for one participant. Some teachers and some students generalized the use of self-monitoring interventions to other activities, students, and target behaviors. Social validity measures indicate that self-monitoring interventions for young children with developmental disabilities are socially important. / text